The present invention relates to a coupling condition monitoring system for monitoring a coupling condition of an engine-driven towing vehicle coupled to an implement.
Various control systems are known for monitoring the condition of a coupling system which couples an implement to a towing vehicle. Such control systems are intended to avoid erroneous operation of coupling attachments that could damage the towing vehicle and/or the implement or even cause injury. Moreover, such control systems help assure an orderly electrical and/or mechanical operation of a coupled towing vehicle/implement. The implement may be a trailer or an agricultural implement.
A system for monitoring a trailer/towing vehicle mechanical coupling is disclosed in DE 196 47 042 A1, wherein a sensor transmits an error signal which causes a blinking light when the towing vehicle is improperly coupled to the implement.
DE 101 35 272 A1 describes a monitoring circuit which senses an error in the connection of a retraction or extension of a coupling element, and prevents any further retraction or extension. A similar system is disclosed by DE 101 04 180 A1 which detects the use of an electric supply and blocks the automatic actuation of an attachment coupling.
DE 44 12 111 A1 discloses an attached coupling system that assures an automatic connection of mechanical as well as electrical couplers.
These known control systems described above monitor the process of coupling an implement to the towing vehicle, but they do not monitor the uncoupling process. However, modern towing vehicles and implements are equipped with costly coupling systems that include electrical and/or hydraulic and/or pneumatic connecting lines, and, in particular, connecting lines for CAN-bus systems. These coupling systems can be damaged by inappropriate uncoupling processes or erroneous operation of the coupling system. For example, an operator could fail to separate the electronic and/or hydraulic and/or pneumatic connecting lines after the mechanical uncoupling of the coupled implement. Also, during operation on a slope the towing vehicle and the implement could move away from each other before the completion of the uncoupling process. An unintended separation of the towing vehicle from the implement after a mechanical uncoupling, but while the electrical, hydraulic and/or pneumatic connections are still intact, can result in damage to the connections and significant repair costs.
Frequently, plug-in connections are designed so that they separate automatically at a certain maximum force. But this may not occur in all operating conditions. If a towing vehicle is separated from a trailer at a significant angle to the trailer, then the plug-in connections may not separate without damage. Other connections cannot be separated without damage.
It would be desirable to have a vehicle/implement coupling system which prevents unintended separation of the vehicle from the implement, as long as a coupling or uncoupling process is not fully completed.